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# frozen_string_literal: true
class Module
# Allows you to make aliases for attributes, which includes
# getter, setter, and a predicate.
#
# class Content < ActiveRecord::Base
# # has a title attribute
# end
#
# class Email < Content
# alias_attribute :subject, :title
# end
#
# e = Email.find(1)
# e.title # => "Superstars"
# e.subject # => "Superstars"
# e.subject? # => true
# e.subject = "Megastars"
# e.title # => "Megastars"
def alias_attribute(new_name, old_name)
# The following reader methods use an explicit `self` receiver in order to
# support aliases that start with an uppercase letter. Otherwise, they would
# be resolved as constants instead.
module_eval <<-STR, __FILE__, __LINE__ + 1
def #{new_name}; self.#{old_name}; end # def subject; self.title; end
def #{new_name}?; self.#{old_name}?; end # def subject?; self.title?; end
def #{new_name}=(v); self.#{old_name} = v; end # def subject=(v); self.title = v; end
STR
end
end
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